Originally Posted by
franklin_m
I would argue the model looks tiny next to the full scale because for the very reason I explained above. As for the other example, it's got to be at both 1/4 the speed AND 1/4 the distance to appear correct. At a distance the eye sees everything as an outline. And surface area is just linear dimensions. Let me do some thinking on that. The other very big factor in vision and perception is what else is in the field of view.
I don't know that volume makes sense, since at any distance we don't "see" the depth of the object.
Surface area is not "just linear dimensions." A square 10 inches on a side has an area of 100 square inches. A square 5 inches on a side has an area of 25 square inches. So the larger square is twice the "size" of the smaller one if you just measure length, but it's four times the area. I'm inclined to think that scale speed ought to relate to the squares of the "scale," because, as you say, you don't fully see depth at a distance. But this is just a guess, not something I'd argue for. My point is just that we shouldn't assume that scale speed for a 1/4 scale model should be 1/4 the speed of the full scale just because of the number we use to label scales. "Quarter scale" is just what we call it; it could just as well be called "1/16 scale" or "1/64 scale." Picking length to compare scales is probably a good thing in the sense of simplifying what we do in building model, but it's not "right" in some "law of nature" sense. I'd bet that if we all built model hot-air balloons instead of airplanes we'd be naming scales by relative volumes. (And we wouldn't have to worry about scale speed.)